1. Technical Field
Embodiments generally relate to electronic circuits, and more specifically to power supply circuits intended for electronic devices (circuits or circuit assemblies) having at least two operating modes requiring different power supply voltages. Embodiments more specifically apply to a power supply circuit for an electronic device having a stand-by mode of lower power consumption than an active mode.
2. Discussion of the Related Art
In many electronic devices, unnecessary power consumption of the power supply circuit during periods when the powered device is not active is desired to be avoided. Several power supply circuits which are activated independently from one another according to needs are generally provided.
Such devices are relatively complex. In particular, they require selectors downstream of rectifying means.
Further, most often, a control signal is issued by the powered device to activate or deactivate the different power supply modes. Such control signals are generally logic signals originating from a microcontroller of the powered device. This requires interface circuits between the powered device and the power supply circuit. Further, this requires additional terminals on the power supply circuit side and on the powered device side.
It would be desirable to have a power supply circuit with a decreased loss, especially in stand-by mode.
It would further be desirable to have a self-contained power supply circuit capable of adapting to the power required by the load, without for a control signal to have to be issued by said load.